I remember learning about dead butt syndrome (DBS) during a presentation at the clinic where I worked several years ago, two years into my career. I believe the sales rep was there to push taping products, but this topic somehow came up. (Please note: while some refer to all the gluteal muscles becoming weak, others specify the gluteus medius muscle in particular.) This gentleman explained that since people sit all day without using their gluteus muscles, they become weak. Made sense to me! And it had a fun name.

However, when I began using the term with patients whose gluteus medius muscles were in fact weak, and fielding patients' questions regarding the topic, I became skeptical. For one, if sitting dormant all day was the root cause, why wouldn't mostmuscles weaken? And, secondly, if it was sitting combined with lack of daily use of the gluteus medius muscles - lack of moving the hips laterally - that was the trigger, wouldn't the lateral movers of other joints suffer then too?So I did a bit of "research:" I read a few articles intended for the public. The consensus is that DBS not only affects expert sitters, but also people who exercise, but who don't target the glute muscles enough. That sounds strange. Those could be very different cohorts. Or, the exercisers could also be expert sitters when they're not moving. Here are my two chief complaints with what I found to be the commonly proposed etiology of DBS:

Asserting that the glutes are weak because of reciprocal inhibition does not resonate with me. This argument states that, with prolonged sitting, hip flexors get tight and contracted and therefore inhibit the muscles opposite them - the glutes. For starters, tight and contracted are not necessarily the same thing. I'll allow that hip flexors may get tight the more we sit with them maintained in a shortened state, but given they get some stretch with each step we take, pathological hip flexor tightness is a hard sell for me. Very often what is diagnosed as hip flexor tightness is actually femoral nerve tightness. (There are clinical tests to distinguish between the two.) Additionally, hip flexors don't contract, that is, actively work, while you're seated. They're normally pretty quiet as you just sit there. Lastly, my understanding is that reciprocal inhibition is when the body momentarily relaxes an antagonist to allow the agonist to do its work - which in and of itself does not create weakness. In sum, while I certainly agree that many people have weak gluteus muscles (one or more of them) I can't get behind this explanation.

One author writes, DBS "can lead to lower back pain and hip pain, as well as knee and ankle issues, as the body tries to compensate for the imbalance." Can weakness lead to pain? Sure. Is it more likely, though, that the weak glutes, low back pain, hip pain, and lower extremity pain are all manifestations of one pathology? That is, most likely a lumbar spine that is a little, or a lot, malaligned? The words "compensate" and "imbalance" are actually my two least favorite words in the world of physical medicine. While it doesn't seem far-fetched to think, "Hey, my left knee has been hurting for awhile and now my right hip is starting to hurt because I'm walking differently," what if we instead asked: What can be causing both left knee pain and right hip pain? You must have a solid diagnosis first. The answer to that question, of course, is almost always the spine.

Another article states, "It may seem bizarre for a muscle to just stop functioning out of nowhere." Yes! It is indeed very bizarre! Except when you recall that nerves send power to muscles ... and when there is a problem with the flow of electricity through those nerves, muscles will stop functioning seemingly out of nowhere! This inhibition-driven weakness, while not normal, is extremely common. (In fact, if I tested the primary muscles of the upper and lower extremities of 100 people, I bet not one person would demonstrate full strength. That means not one person would have uninterrupted flow of electricity from their spine to their muscles.) The good news is, once you restore the flow of electrical power from the spine - I use specific movements with my patients to accomplish this - muscles should immediately regain normal strength.​So what is going on with DBS? In the large majority of cases, prolonged sitting (the more slouched, the worse) creates a malalignment in the low back which impedes the flow of electricity via the nerves to the glutes, depriving them of their juice to be strong. The same scenario can create pain in the glutes as pinched nerves can carry pain along their path (or any altered sensation such as tingling or degrees of numbness). That'swhy your butt is dead. To fix it, you'll need to address your low back in order to decompress the nerves. And then, once the power is back on, if your gluteus muscle strength doesn't return completely since the muscles had been dead for so long, you can move on to targeted strengthening exercises to rebuild them. -- Laura